Why does rain make us sleepy?
Lack of sunshine may also be keeping you from sleeping. People feel more awake and upbeat as a result of this. On a rainy day, the absence of light might have the opposite effect, making individuals feel sleepy or down.
Lower oxygen levels in the atmosphere
Our brains may be stimulated and feel refreshed by oxygen. Because more water vapor is in the air during rain, there is less air pressure and less oxygen overall. People will feel drowsy in such a condition as their brains will become less active.
Rainy day humidity also has an impact. The atmosphere outside is dense when it rains. The body must therefore use more effort to maintain equilibrium. This may be exhausting, which is why many people try to get a few additional minutes of sleep.